Re: [PATCH net-next v7 2/2] net: dsa: mv88e6xxx: add support for credit based shaper

[Jakub Kicinski]

On Mon, 15 Jun 2026 16:29:34 +0200 Cedric Jehasse wrote:
> > > +static int mv88e6xxx_setup_tc_cbs(struct dsa_switch *ds, int port,
> > > +				  struct tc_cbs_qopt_offload *cbs)  
> > 
> > please stick an extack into struct tc_cbs_qopt_offload and use it to
> > report the reason for rejection back to the user
> 
> Do you mean modifying cbs_enable_offload to report a driver specified reason isof
> reportig the generic "Specified device failed to setup cbs hardware offload"?
> What should be done for other drivers who handle TC_SETUP_QDISC_CBS, but don't
> fill in extack? Should cbs_enable_offload fill in extack with "Specified device
> failed to setup cbs hardware offload"?

There's a "weak" version of the extack-setting macro which you can use
to avoid overriding the driver-specified message. With that you should
be able to set the generic error for existing switches while allowing
your driver to provide more specific reason.

BTW please note that net-next is now closed for the duration of the
merge window.